Men who have sex with men (MSM) are at increased risk of anal cancer as a result of prevalent anal human papillomavirus (HPV) infection in this population. Prophylactic vaccination is a potentially effective public health strategy for preventing anal cancer. A quadrivalent vaccine is currently approved for the prevention of anal cancer and anal squamous intraepithelial lesions in both males and females. As a result, routine vaccination is recommended for all MSM up through at 26. Maximizing vaccine uptake among populations of MSM will require public health interventions to address factors influencing vaccine acceptability, intentions, and subsequent behavior. Currently, public health educators have limited information available to effectively tailor health education messages and interventions aimed at increasing HPV vaccine uptake among vaccine-eligible adult MSM. The Integrative Model of Behavioral Prediction (IM) is a viable theoretical framework from which to understand HPV vaccine decision-making and to guide social and culturally tailored interventions. According to this model, health education interventions must address the salient HPV-related beliefs and perceptions expressed by young MSM in order to effectively promote vaccination. The long-term goal of this research is to decrease the incidence of anal cancer among MSM by preventing infection of HPV types -16 and -18 through vaccination. The purpose of the proposed research is to understand the factors important to young MSM when making decisions about HPV vaccination by addressing the following specific aims: (1a) Describe salient outcome, normative, and control beliefs related to HPV vaccination among young MSM; (1b) determine factors that underlie these beliefs through semi-structured qualitative interviews and a structured open-ended qualitative survey; (2) explore the influence of socio-demographic characteristics, such as age and racial/ethnic background, in HPV vaccine decision-making among young MSM; and (3) identify information needs and trusted sources of information regarding HPV vaccination among young MSM. These objectives will be addressed in a multi-method sequential qualitative study including semi-structured interviews (Phase 1) and an open-ended qualitative survey (Phase 2) of MSM 18 to 26 years old. The proposed research will reinforce the applicants training plan in cancer epidemiology, the public health needs of lesbian, gay, bisexual and transgender populations, and the use of qualitative methods in health education research. Through a combination of coursework, directed study, and mentorship from his sponsorship team, the proposed training plan will ensure that the applicant will obtain the level of knowledge and skills necessary to build a program of research that will address the critical public health needs of LGBT populations.